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00019 #ifndef __CS_MATH_H__
00020 #define __CS_MATH_H__
00021
00022 #include "csutil/algorithms.h"
00023
00034 template<class T>
00035 const T& csMax (const T& a, const T& b)
00036 {
00037 if (b < a) return a;
00038 return b;
00039 }
00040
00044 template<class T>
00045 const T& csMin (const T& a, const T& b)
00046 {
00047 if (a < b) return a;
00048 return b;
00049 }
00050
00054 template<class T>
00055 void csSort (T& a, T& b)
00056 {
00057 if (b < a)
00058 CS::Swap (a, b);
00059 }
00060
00065 template<class T, class U>
00066 void csSort (T& a, T& b, U& x, U& y)
00067 {
00068 if (b < a)
00069 {
00070 CS::Swap (a, b);
00071 CS::Swap (x, y);
00072 }
00073 }
00074
00075
00079 template<class T>
00080 T csClamp (const T& a, T max, T min)
00081 {
00082 return csMin (csMax (a, min), max);
00083 }
00084
00090 template<class T>
00091 T csSmoothStep (const T& a, T max, T min)
00092 {
00093 T tmp, tmp2;
00094 if (a <= min)
00095 tmp = 0.0f;
00096 else if (a >= max)
00097 tmp = 1.0f;
00098 else
00099 {
00100 tmp2 = (a - min) / (max-min);
00101 tmp = tmp2*tmp2 * (3.0 - 2.0*tmp2);
00102 }
00103 return tmp;
00104 }
00105
00110 template<class T, class Tfactor>
00111 T csLerp (const T& a, const T& b, const Tfactor& f)
00112 {
00113 return (a + (b - a) * f);
00114 }
00115
00119 template<class T>
00120 T csSquare (const T& x)
00121 {
00122 return x * x;
00123 }
00124
00125 namespace CS
00126 {
00129
00130
00131
00132
00134 CS_FORCEINLINE bool IsNaN (float f)
00135 {
00136 #ifdef CS_IEEE_DOUBLE_FORMAT
00137 const uint32 exponentMask = 0x7f800000;
00138 const uint32 mantissaMask = 0x007fffff;
00139 union
00140 {
00141 float f;
00142 uint32 ui32;
00143 } u;
00144 u.f = f;
00145 return ((u.ui32 & exponentMask) == exponentMask)
00146 && ((u.ui32 & mantissaMask) != 0);
00147 #else
00148 #error Do not know how to test for NaN
00149 #endif
00150 }
00151
00152 CS_CRYSTALSPACE_EXPORT bool IsNaN_ext (double d);
00154 CS_FORCEINLINE bool IsNaN (double d)
00155 {
00156 #ifdef __STRICT_ANSI__
00157 return IsNaN_ext (d);
00158 #else
00159 #ifdef CS_IEEE_DOUBLE_FORMAT
00160 const uint64 exponentMask = CONST_UINT64(0x7ff0000000000000);
00161 const uint64 mantissaMask = CONST_UINT64(0x000fffffffffffff);
00162 union
00163 {
00164 double d;
00165 uint64 ui64;
00166 } u;
00167 u.d = d;
00168 return ((u.ui64 & exponentMask) == exponentMask)
00169 && ((u.ui64 & mantissaMask) != 0);
00170 #else
00171 #error Do not know how to test for NaN
00172 #endif
00173 #endif
00174 }
00175
00177 CS_FORCEINLINE bool IsFinite (float f)
00178 {
00179 #ifdef CS_IEEE_DOUBLE_FORMAT
00180 const uint32 exponentMask = 0x7f800000;
00181 union
00182 {
00183 float f;
00184 uint32 ui32;
00185 } u;
00186 u.f = f;
00187 return ((u.ui32 & exponentMask) != exponentMask);
00188 #else
00189 #error Do not know how to test for NaN
00190 #endif
00191 }
00192
00193 CS_CRYSTALSPACE_EXPORT bool IsFinite_ext (double d);
00195 CS_FORCEINLINE bool IsFinite (double d)
00196 {
00197 #ifdef __STRICT_ANSI__
00198 return IsFinite_ext (d);
00199 #else
00200 #ifdef CS_IEEE_DOUBLE_FORMAT
00201 const uint64 exponentMask = CONST_UINT64(0x7ff0000000000000);
00202 union
00203 {
00204 double d;
00205 uint64 ui64;
00206 } u;
00207 u.d = d;
00208 return ((u.ui64 & exponentMask) != exponentMask);
00209 #else
00210 #error Do not know how to test for NaN
00211 #endif
00212 #endif
00213 }
00214
00216 CS_FORCEINLINE float Infinity()
00217 {
00218 #ifdef CS_IEEE_DOUBLE_FORMAT
00219 union
00220 {
00221 uint32 ui32;
00222 float f;
00223 } u;
00224 u.ui32 = 0x7f800000;
00225 return u.f;
00226 #else
00227 return std::numeric_limits<float>::infinity();
00228 #endif
00229 }
00231 }
00232
00234
00238 CS_DEPRECATED_METHOD_MSG("Use CS::IsFinite(x) instead")
00239 CS_FORCEINLINE bool csFinite (float f)
00240 {
00241 return CS::IsFinite (f);
00242 }
00247 CS_DEPRECATED_METHOD_MSG("Use CS::IsFinite(x) instead")
00248 CS_FORCEINLINE bool csFinite (double d)
00249 {
00250 return CS::IsFinite (d);
00251 }
00252
00257 CS_DEPRECATED_METHOD_MSG("Use CS::IsNaN(x) instead")
00258 CS_FORCEINLINE bool csNaN (float f)
00259 {
00260 return CS::IsNaN (f);
00261 }
00266 CS_DEPRECATED_METHOD_MSG("Use CS::IsNaN(x) instead")
00267 CS_FORCEINLINE bool csNaN (double d)
00268 {
00269 return CS::IsNaN (d);
00270 }
00271
00277 CS_DEPRECATED_METHOD_MSG("Usage not recommended, inconsistent results")
00278 CS_FORCEINLINE bool csNormal (float f)
00279 {
00280 #if defined (CS_HAVE_NORMALF)
00281 return normalf (f);
00282 #elif defined (CS_HAVE_STD__ISNORMAL)
00283 return std::isnormal (f);
00284 #elif defined(CS_HAVE_ISNORMAL)
00285 return isnormal (f);
00286 #else
00287 return CS::IsFinite(f) && !CS::IsNaN(f);
00288 #endif
00289 }
00295 CS_DEPRECATED_METHOD_MSG("Usage not recommended, inconsistent results")
00296 CS_FORCEINLINE bool csNormal (double d)
00297 {
00298 #if defined (CS_HAVE_STD__ISNORMAL)
00299 return std::isnormal (d);
00300 #elif defined(CS_HAVE_ISNORMAL)
00301 return isnormal (d);
00302 #else
00303 return CS::IsFinite(d) && !CS::IsNaN(d);
00304 #endif
00305 }
00307
00308
00309 namespace CS
00310 {
00311 namespace Math
00312 {
00314 template<typename T>
00315 CS_FORCEINLINE_TEMPLATEMETHOD T NextModulo3 (T number)
00316 {
00317 return (1 << number) & 0x3;
00318 }
00319 }
00320 }
00321
00322
00325 #endif //__CS_MATH_H__